IEEE Transactions on Applied Superconductivity

Silicon Membrane-Based Waveguide-to-Superconducting CPW Transitions at 2 mm Band

Akihiro Masukura, Wenlei Shan, Shohei Ezaki, Takafumi Kojima, Taku Nakajima, Akira Mizuno

Published Apr 14, 2023• 3 citations

Abstract

In millimeter and submillimeter superconducting receivers, which are widely applied in radio astronomical observations, waveguide-to-planar transmission line transitions are key components connecting waveguide medium and the superconducting planar circuit. Although conventional quartz substrate-based transitions perform well for single-pixel receivers, these waveguide probes are not suitable for imaging arrays because their narrow chip space prohibits a higher degree integration of superconducting circuits. For multi-beam receiving applications, we have demonstrated fully functional monolithic microwave integrated circuit superconductor-insulator-superconductor (SIS) mixers with on-chip silicon membrane-based transitions at 2 mm wavelengths. In the present work, we aim to assess the transition as a stand-alone component and investigate its bandwidth potential. We designed a full-height waveguide transition which covers 125–211 GHz, more than 50% fractional bandwidth. The experimental study was carried out by performing cryogenic measurements of the transmission of a back-to-back probe pair with a mm-wave network analyzer. The measured transmission is well consistent with the simulated one in the frequency range of 125–170 GHz, which is covered by the network analyzer in this measurement.

DOI: 10.1109/tasc.2023.3267331

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